Tertiary phosphine oxides



United States Patent ()1 ice 3,454,650 Patented July 8, 1969 3,454,650 TERTIARY PHOSPHINE OXIDES Sheldon Buckler, Lincoln, Mass., and Martin Epstein, Stamford, Conn., assignors to American Cyanamid Company, Stamford, Conn., a corporation of Maine No Drawing. Continuation-impart of application Ser. No. 176,776, Mar. 1, 1962. This application May 9, 1966, Ser. No. 548,433

Int. Cl. 'C07f 9/50 US. Cl. 260-6065 6 Claims ABSTRACT OF THE DISCLOSURE Tertiary phosphine oxides of the formula where, typically, R is phenyl, R is hydrogen, alkyl or phenyl, and R" is alkyl or phenyl. The compounds are useful heavy metal sequestering agents.

This application is a continuation-in-part of application Ser. No. 176,776, filed Mar. 1, 1962 and now abandoned. The present invention relates to tertiary phosphine oxides of the formula I? RzP--C wherein R represents phenyl, para-chlorophenyl, 2- hydroxyethyl-, and

R"O( )CHzCH2 wherein R is lower alkyl (C -C R is hydrogen, alkyl having from 1 to 8 carbon atoms, or phenyl, R" represents alkyl having 1 to 8 carbon atoms, phenyl, para-substituted phenyl, or naphthyl; the sum of R and R taken with of the product formula also represents cyclopentyl, cyclohexyl, or l-indanyl; provided that when one of R and R is phenyl, the other of R and R is other than hydrogen.

These products are prepared by the reaction of a weakly basic secondary phosphine of the formula R PH,

which secondary phosphine has a pK less than 2, with d a ketone or aldehyde of the formula and the corresponding tertiary phosphine oxide prepared as follows:

Cone.

Ca -C The reactants of the present invention may be brought together in almost any sequence. While stoichiometric amounts of these reactants react to form the products of the present invention, it is not critical or necessary to have stoichiometric amounts present. Any surplus of any reactant with respect to the other may be present without affecting the nature of the reaction. Obviously, too large a surplus is both cumbersome and impractical.

While reaction is generally carried out at room temperature (20 C.25 C.), temperatures in the range of 0 C. to C. may be employed. In addition, atmospheric, sub-atmospheric or super-atmospheric pressures may be employed without changing the nature of the reaction.

Typical aldehyde and ketone reactants within the purview of the instant invention are cyclopentanone, cyclohexanone, l-indanone, dimethyl ketone, dibutyl ketone, ethylbutyl ketone, dioctyl ketone, diethyl ketone, dipropyl ketone, dipentyl ketone, dihexyl ketone, diheptyl ketone,

acetaldehyde, propionaldehyde, isobutylaldehyde, heptaldehyde, octaldehyde, benzaldehyde, parachlorobenzaldehyde, para-bromobenzaldehyde, para-hydroxybenzaldehyde, para-(lower)alkoxybenzaldehyde, naphthaldehyde, benzophenone, acetophenone and the like.

Typical secondary phosphines which are weakly basic and have a pK less than 2 are diphenylphosphine, bis- (2-hydroxyethyl phosphine, bis (parachlorophenyl phosphine, and the like.

Further, it has been found according to the present invention that bis(2-cyanoethyl)phosphine, when reacted with the carbonyl compounds contemplated herein, reacts as defined above, yet with one modification:

Cone. (ONCHzOHmPH CH3(CHz)5CHO HK As is evident from this embodiment the CN moiety of bis(Z-cyanoethyl)phosphine is converted to COOH.

The present invention will best be understood from the following examples which are intended to illustrate and not limit the scope of the invention:

Example I.--Diphenylcyclopentylphosphine oxides Into a flask purged with nitrogen is placed one part of cyclopentanone dissolved in 50 parts concentrated hydrochloric acid. One part of diphenylphosphine is added thereto and the resulting solution refluxed for two hours. A two layer mixture forms which is diluted with water and extracted with chloroform. Upon evaporating the chloroform from the extracted material a solid residue results. This product residue is then recrystallized from normal hexane and is identified as diphenylcyclopentylphosphine oxide.

Example II.Diphenylcyclohexylphosphine oxide Example I is repeated in every essential respect with the exception that cyclohexanone is substituted for cyclopentanone. The corresponding tertiary phosphine oxide, diphenylcyclohexylphosphine oxide, is recovered as taught in Example I.

Example 1II.Diphenyl-l-indanylphosphine oxide Example I is repeated in every essential respect with the exception that cyclopentanone is substituted with 1- indanone.

should be at least a minimum of 10% water in the aqueous acid solution.

Clearly, the instant discovery encompasses numerous modifications within the skill of the art. Consequently, while the present invention has been described in detail Examples IV-XXX 5 with respect to specific embodlments thereof, it is not In the following table the reactants and reaction con- Intended that these details be construed as limitations ditions of Example I, above, are modified as shown in upon the scope of the invention except insofar as they order to further illustrate the instant discovery: appear in the appended claims.

TABLE H ll R2PH :0 RzP-CH BK \RII Molar Example Secondary ny Cone. ratio Temp., phosphine compound acid AA:B C. Tertiary phosphine oxide (A) (B) (C) v Bis -chiorophenyl)phosp oc yde H01 1:2 120 Bis(lgehlorophenyl)octylphosphi 0x1 e. v Bis(z-hydroxyethyl)phosp e d o e H1804 2:1 80 Bisg-hylglroxyethyl)-1-indany1- p osp ine oxide. VI Y YDD P Cyclohexanone HaPO4 2:1 115 BisZ-cagboxyetlayl)cyclohexylp osp me 0x1 e. VII Diphenylphosphine Dlmethyl ketone H 1 5:1 Diphenylisopmpylphosphme 0mm III Bis(2-carboethoxyethyl)phosph1ne.. Dipropyl ketone H01 1:3 5 Bis2-ca{1lgoethqi r1yethyl)-4-heptylp osp me 0x1 e. 1X Bis(2-earbopropoxyethyl)phosphme. Dloctyl ketone HBr 1:1 120 Bis(2carbopropoxyethyl)-9-heptadecylphosphine oxide. X Bis(zearbobutoxyethyl)phosphm Ethyl utyl k ton H1801 1:3 75 Bisg-cailbobutoyethyl)-3-hept p osp ine 0x1 9. X1 Bis(zearbomethoxyethyl)phos- Acetald yd H01 1:5 Bis(2-carbornethoxyethy1)ethylphine. phosphine oxide. X11 Diphenylphosp P pw y 28 4 7:1 Diphenylpropylphosphine oxida 11 Bis(2-earbomethoxyet y1)p s- Be a d yd HCI 1:1 65 Bisg-carlbomethcfxyethyl)benzylphine. p osp ine oxi e. XIV Bis(p-chlorophenyl)phosphme.-... p-Chlorobenza1dehyde H 1 0, 1:2 60 Bisfpilchlofiophemg)- hl yp osp me OX1 B. XV Bis(2-hydroxyethyl)phosphme p-Bromobenzaldehyde... HaP04 2:1 30 Bisl(2iliydil oxyethyl)-p-bromobenzy p osp line oxide. XVI Bis(2-cyanoethyl)phosphine D- Y Y alde- H61 3:1 60 Bis(2-earboxyethyD-p-hydroxyhyde. benzylphosphine oxide. XVII Di henylphosphme p-Ethoxy nzald hyde.- H1804 3:1 120 Diglhenyl-pethoxybenzylphosp 1116 OX1 G. XVIII do py yde- 2 04 1:1 25 Dipkl'lenyl-pcibutoxybenzylphosp me oxi e. XIX Bis(p-chlorophenyl)phosphine l-naphthaldehyde H01 1:1 130 Bis(p-chlorophenyl)-1-naphthy1- I methylenephosphine oxide. XX Bis(z-hydroxyethyl)phosphme Benzoph non HCl 1:2 Bisfzfii di x ethyli)ah n l yp osp me 0X1 e. XXI ni hen lphosphine Ac p H01 1:1 90 Diiilhenyl(ogmethylbenzybphosp me 0x1 e. XXII Bis(cyanoethyl)phosp i n ep a y H0 1:1 Bisg-carbogyethyl)-heptylph05- p me 0x1 e. III Di henyl hosphine Cy l p t H01 1:1 Diphgnylcyclopentylphosphine OX1 6. do -i da o e H01 80 Diphanyl-l-indanylphosphine 0X 6. 1-naphthaldehyde... HCl 1:1 100 Diphgnyl-l-naphthylphosphine OX1 e. Diethyl ketone 1101 1:1 120 Diphenyl-S-pentylphosphine oxide. Benzaldehyde... HCI 2:1 75 Diphenylbenzylphosphine oxide.

Isobutylaldehyde HCl 1:1 120 Diphenylisobutylphosphine oxide. do" n-Heptylaldehyde. 1101 1:1 120 Diphenyl-l-heptylphosphine oxide. do Acetaldehyde H01 132 80 Diphenylethylphosphin id The compounds of the present invention are particularly We claim:

useful as sequestering agents in the selective removal of heavy metal values from mixtures containing ions, such as uranyl. Uranyl values can be selectively leached from an ore containing the same by employing techniques known in the art, as shown by Blake et al. in the Atomic 7 Energy Commission Report ORNL1903, May 13, 1955.

1. A tertiary phosphine oxide of the formula By concentrated mineral acid herein is intended a strong mineral acid having at least 8 molar concentration of the acid in aqueous solution. While no lower than about wherein R is phenyl, para-chlorophenyl, or 2-hydroxyethyl; R is hydrogen, alkyl (C C or phenyl; R" is alkyl (C C phenyl, para-substituted phenyl or naphthyl,

8 molar acid concentration is contemplated herein, there 75 said substituents for para-substituted phenyl being halogen, hydroxy or lower alkoxy; and the sum of R and R" taken with CE I Jan

of the product formula is l-indanyl.

3. The tertiary phosphine oxide of claim 1 wherein R is Z-hydroxyethyl and each of R and R" is phenyl.

4. The tertiary phosphine oxide of claim 1 wherein R is phenyl, R is hydrogen, and R is para-ethoxyphenyl.

5. The tertiary phosphine oxide of claim 1 wherein R is para-chlorophenyl, R is hydrogen, and R" is parachlorophenyl.

6. The tertiary phosphine oxide of claim 1 wherein R is para-chlorophenyl, R is hydrogen, and R" is naphthyl.

References Cited UNITED STATES PATENTS 2,864,668 12/1958 Baldwin et a1. 260606.5 XR 3,213,057 11/1965 Ritt et a1 260606.5 XR

OTHER REFERENCES Buckler et al.: J.A.C.S., vol. 82. (1960), pp. 2076 to 2077.

Berlin et 211.: Chemical Reviews, vol. 6, No. 3 (1960), p. 256.

TOBIAS E. LEVOW, Primary Examiner.

W. F. W. BELLAMY, Assistant Examiner.

US. Cl. X.R.

32 3 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 454, 550 Dated January 22, 1970 Inventor(S) SHELDON BUCKLER and MARTIN EPS'I'EIN It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 2, line 7', the formula should read:

Column 2, line 29-50, cancel parachlorohenzaldehyde" and substitute therefore --parachlorobenzaldehyde-.

SIGNED AND SEALED MAY 1 21970 (5 Attest:

L Edward Flmlm' wmwr E. 5mm .m.

Atlegting Officer 00111121551011" of 

